Higher brilliance X-ray sources are required for applications in X-ray diffraction, tomography, and lithography. In current designs, the maximum power loading and the resulting brilliance are limited by the heat transfer capabilities of copper anode material. A novel heat spreader is proposed. Significantly higher brilliance and power capability is anticipated by retrofitting the annular heat spreader onto existing rotating anodes. Phase I development effort focuses on the heat spreader design, materials and fabrication issues. A proposed heat spreader will be tested in a relevant environment to obtain comparative data on power, brilliance and focal spot temperature. The results will be interpreted with a thermal model accounting for relevant heat transfer effects. A Phase II goal is the development of a prototype high-brilliance gold anode for use in Anomalous Dispersion Protein Crystallography.